different kind of Tri Bike question

Not that I have ever heard of. The only way I can think that they would allow it is if it was medically necessary.

Would it meet these 2 criteria from USA Tri rules sec 5.11(c)A vertical line touching the front most point of the saddle may be no more than 5 centimeters in front of and no more than 15 centimeters behind a vertical line passing through the center of the chain wheel axle, and the cyclist must not have the capability of adjusting the saddle beyond these limits during competition.(d) The "front-to-center" distance, which is defined as the distance between a vertical line passing through the center of the chain wheel axle and a vertical line passing through the center of the front axle, must measure not less than 54 centimeters and no more than 65 centimeters, except that in the case of bicycles for taller participants (where the distance between the center of the chain wheel axle and the top of the saddle is greater than 80 centimeters), the front-to-center distance cannot exceed 68 centimeters and, in the case of bicycles for shorter cyclists (where the distance between the center of the chain wheel axle and the top of the saddle is less than 71 centimeters), the front-to-center distance cannot be less than 50 centimeters. Applicability of the two foregoing exceptions is determined by measuring from a point on top of the saddle which is 14 centimeters behind the front most point of the saddle.